fnd flexsql in a report into SQL statement.

Do somebody knows how this work ?
I found this in a program units of a reports which belong to Oracle Financial PO module.

I think tat it is used to check if values belong to a fork : seg1.seg2.seg3 between seg1inf and seg1sup, seg2inf and seg2sup, seg3inf and seg3sup.

Iwould like to convert it into a SQL statement.

  SRW.USER_EXIT('FND FLEXSQL CODE           ="MCAT"
                             OUTPUT         =":P_WHERE_CAT"
                             APPL_SHORT_NAME="INV"
                             MODE           ="WHERE"
                             DISPLAY        ="ALL"
                             NUM
=":P_STRUCT_NUM"
TABLEALIAS     ="MCA"
                             OPERATOR       ="BETWEEN"
                             OPERAND1       =":P_CATEGORY_FROM"
                             OPERAND2       =":P_CATEGORY_TO"');